PowerPoint Presentation - T0/TOF Update Time Stability

Frank L. H. Wolfs

Department of Physics and Astronomy, University of Rochester

Commissioning T0 Counters

•The main task is to align the T0 counters in time using the time equalizer.

•Procedure:

•Disable all but 1 T0 counter on either side.

•Measure the time of the OR for either side:

•Need collisions.

•Need to correct for the vertex dependence (vertex position influences timing of START and STOP).

•The width of the timing peak will be determined by jitter in START.

•We need 500 - 1000 collisions to be able to determine the centroid with an accuracy of better than 100 ps.

•Repeat the same measurement for all 10 T0 counters on either side.

•Determine appropriate delays for each channel and verify that correct delays are assigned by repeating this sequence of measurements.

•This procedure requires a silicon vertex.